Crepe thread and fabric containing artificial filaments



Patented Jan. 3,1939.

CREPE THREAD AND FABRIC CONTAINING ARTIFICIAL FILAMENTS Henry Dreyfus,London, and Robert Wighton Moncriefl, Sidney James Menaer and Thomas,

Eccles, Spondon, near Derby, England, assignors to Celanese Corporationof America, a cor-' poration of Delaware No Dra wing. ApplicationJanuary 31, 1935, Serial No. 4,302. In Great Britain February 8, 1934This invention relates to the manufacture of crepe threads and fabrics,and has for its particular object the production of crepe fabrics of Ian improved character from threads containing 5 artificial filaments.

Fabrics exhibiting crepe eilects have long been obtained by employing intheir construction highly twisted threads of natural silk in the gummedstate," the crepe eflects appearing moreparticui larly when the fabricso formed is subjected to an aqueous scouring treatment. The fabricsobtained by this process are highly valued on account oftheir pleasingappearance and handle.

The production of crepe fabrics in an analogous l manner by the use ofthreads containing artificial filaments has, however, been accompaniedby dif- .ficulties in various directions, particularlyas regards'tbestrength and appearance of the fab-,

rics. 2n It has now been found that considerable improvement can'beeil'ected by employing crepe threads containing artificial filamentswhich have been stretched, i. e. given a permanent elongation. Suchstretched threads may be of a cellu- 2 losic character, or they mayconsist of organic derivatives of cellulose, for example celluloseacetate or other organic cellulose esters such as cellulose formate,propionate, butyrate, and oxyethyl cellulose acetate, and celluloseethers such so as ethyl and benzyl cellulose,

For example, cellulose acetate threads may be employed which have beenstretched to 120, 130, 150, 200, 300, 500% or more of their originallength, for example by subjecting. them to the action of softeningagents such as acetone, or

ethylene methylene ethendioxaneand similar .cyclic ethers, ethyl ormethyl alcohol, or formaldehyde, diluted, if desired, e. g. with water,to bring them into a condition to undergo stretching of the ordermentioned. Thus, cellulose acetate threads may with advantage bestretched by about 30% of their original length in the presence offormaldehyde.

there may be employed cellulose deriva- 4'5 tive threads which have beenproduced by wet spinning operations in which a high degree of stretch isapplied to the extruded filaments during coagulation. Whatever themethod employed to stretch the 50 threads, it should be such as to givethem a tenacity of at least 2 grams per denier, and preferably more, e.g. 3, 4, or more grams per denier.

Besides considerable fineness of filament denier, cellulose derivativethreads stretched as llabove described have a strength that is of valuewhen the threads are subjected to the high degree of twisting necessaryfor the production of But apart from the possibility'of stronger crepethreads and fabrics being pro,- 'duced; it is also found thatconsiderable im- 5 Movement in crepe effect results from the use of suchthreads, there being obtained a fine, well-marked crepe eilect similarto that ordinarily obtained by the use of natural silk crepe threads. s10 The threads to be stretched may have normal or bright lustre, or theymay be threads having areduced or subdued lustre. For example, where thecrepe threads are desired to have a dull appearance, the threads to betreated may with is advantage contain a certain amount of pigment,

e. g, 1, 2 or 3% of their weight, in accordance with the dullnessrequired. Thus, cellulose acetate threads containing, e. g. in theproportions above indicated, antimony oxide, stannic oxide, or titaniumoxide may be employed according to the invention.

The cellulose derivative threads may with advantage be formed fromcellulose derivatives of high viscosity characteristics; for examplethere may be employed cellulose acetate or other cellulose esters asdescribed in U. -S. Patent No. 1,708,787. Thus the cellulose acetateshould have a viscosity of at least and preferably exceeding 50, forexample of the order of 75, 100,150, or even 200 or more as measured bycomparing theviscosity'of a 6% solution of the cellulose acetate inacetone with that of glycerine taken as a standard of 100.

After the stretching treatment the threads may then be subjected to ashrinking treatment with the object of restoring in part at least a lossof extensibility resulting from the stretching operation.

The filaments contained in the threads may m be continuous ordiscontinuous in character.

As above stated the stretched threads employed according to theinventionmay be of a cellulosic character, e. g. viscose and nitrocellulosethreads. Particularly useful threads are those consisting of regeneratedcellulose produced by eifecting saponification of cellulose acetate orother cellulose ester threads which have undergone a stretchingtreatment as above described. Such saponification' may be complete oronly to partial. In partially saponified materials the saponificationmay be superficial, i. e. the materials may comprise a superficial layerconsisting substantially of cellulose or of esters of cellulose of lowacyl content, and a core of substantially materials in whichsaponification has extendedconsiderably below the surface or eventhroughout the whole section of the material. The saponification may beof a very low order, for example sufficient to produce a loss in weightof 5% or even less. Specially valuable results are obtainable byemploying materials which have been sapcnified. so as to effect a lossof weight of between 5 and 20%, and particularly between 8 and 12%.Products of this type in which the saponiflcation extends considerablybelow the surface or throughout the whole of the material are speciallyrecommended. On the other hand, saponificationmay beof a much higherorder, involving a loss of weight of 30, 40 or even 50% or more,according to the ester content of the initial material, up to completesaponification.

The saponified materials may acquirean ailinity for cotton dyestuffs bythe saponiflcation treatment which may, or may not, involve loss ofaffinity for cellulose ester dyes, for example dyes of the dispersedinsoluble type. It has been found of particular advantage in connectionwith cellulose acetate to carry the saponification to such an extentthat the material is insoluble in acetone but yet retains a relativelyhigh acetyl content.

The stretched cellulose ester threads which have been completely orpartially saponified may consist of materials of high viscositycharacteristics or of materials having normal viscosities.

The degree of twist applied to the threads according to the inventionmay vary within wide limits; for example twist from 45 to '75 or moreturns. per inch may be applied, it being underfstood'that in generalthefiner the thread the 7 higher the degree of twist required. Apart from."'th is fthe, degree of twist desirable in anyparticular'case dependsupon a'number of other ctors, including the precise effects required,thf niaterlalof the filaments, and the fineness of thegfllaments in thethreads. It is to, be-pointed ltpi'n this connection that thefinenessof'the individual fllamentsin the threads-resulting from s oficonsiderable advantage in" bringing out a "oodfcrepe effect on the finalfabric, as well as ding itself to the production ;of fabric havingsoftshandle.

They-twist is conveniently applied by means of anapparatus in which thethread is drawn oil! over the end of a rotating packagekto a guidesubstantially in line with the axis of the package, thereupon led tostake-up device collecting the yarn at a predetermined speedwhich'jdetermlne's 'in accordance with the rate of rotation rotatingbobbin may be provided-'witha fiye'rto guide the thread from thepackage, or with advantagethetwisting device may be provided withmeans'on an extension of 'the spindle projecting beyond the package topreventtwist which has been inserted running-back to the yarn on the 5package, as described in-U. 8. Patent No. 1,784,581.

tli extension effected in the stretchingioperation of the package thedegree of twist applied. The

During twisting the thread may' be subjected to the action of wet steam,as by passing it through a steam box disposed between the guide abovethe spindle and the take-up package. Thread twisted in this way has afinal strength considerably higher than that obtained by twistinguntreated thread. The tension maintained during twisting may be such asunder the action of the applied steam to stretch the thread stillfurther and overcome in part at least the tendency of the thread toincrease in denier during twisting. However, even if the twist isallowed to give a denierincrease, higher final tenacitles are obtained.

The improved crepe threads according to the invention may be applied inany desired manner in the weaving of crepe fabrics either in the weft orwarp or both and with any suitable disposition as regards threads havingleftand righthand twists, as for example leftand right-hand twistsalternating singly or in pairs in the weft. The threads may also be usedotherwise than in woven fabrics; for example, they may be knitted.

What we claim and desire to secure by Letters Patent is:-

1. Process for the production of crepe threads, which comprisesstretching cellulose derivative threads in the presence of an organicsoftening agent for the substance of the threads, and thereaftertwisting the threads to a high degree.

2. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads in the presence of an organicsoftening agent for the cellulose acetate, and thereafter twisting thethreads to a high degree.

3. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads in the presence of an organicsoftening agent for the cellulose acetate to give them a tenacity of atleast 2 grammes per denier, and thereafter twisting the threads to ahigh degree.

4. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads in the presence of an organicsoftening agent for the cellulose acetate to give them a tenacity of atleast 3 grammes per denier, saponifying the threads so as to effect aloss of weight of between 5 and 20% of the cellulose acetate, andthereafter twisting the threads tos. high degree.

5. Process for the production of crepe threads, which comprisesstretching cellulose derivative threads in the presence of'an organicsoftening agent for the substance of the threads. and thereaftertwisting thethreads to a'high degree while applying steam thereto at thepoint where the twist is inserted, f f

j 6. Process forthe production of crepe threads, which comprisesstretching cellulose acetate threads in the presence of an organicsoftening,

agent forthe cellulose acetate and thereafter twisting the threads to ahigh degree while applying steam thereto at the point where the twist isinserted.. T .I

7. Process for the'production of crepe threads,

which comprises stretching, cellulose acetate threads in the presence ofan orgs. nic softening agent for the cellulose-'acetate todfgive them atenacity of at least 2 grammes; per denier; and

thereafter twisting the threads to a high degree while applying steamthereto at the point where the twist is inserted.

8. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads in the presence of 'an organicsoftening agent for the cellulose-acetate to give them a tenacity of atleast 3 grammes per denier, saponifying the threads so as to efiect aloss of weight of between 5 and 20% of the cellulose acetate, andthereafter twisting the threads to a high degree while applying steamthereto at the point where the twist is inserted.

9. Process for the production of crepe threads, which comprisesstretching cellulose acetate threadsin the presence of acetone andthereafter twisting the threads to a high degree.

10. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads in the presence of dioxane andthereafter twisting the threads to a high degree.

11. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads in the presence of formaldehyde andthereafter twisting the threads to a high degree.

12. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads by about 30% of their originallength in the presence of formaldehyde and thereafter twisting thethreads to ,a high degree.

13. Process for the production of crepe threads, which comprisesstretching cellulose ester threads in the presence of an organicsoftening agent for the substance of the threads, at least partiallysaponifying the threads, and thereafter twisting the threads to a highdegree.

14. Process for the production of crepe threads, which comprisesstretching threads of cellulose esters of high viscosity characteristicsin the presence of an organic softening agent for the substance of thethreads, at least partially saponifying the threads, and thereaftertwisting the threads to a high degree.

15. Process for the production of crepe threads, which comprisesstretching threads of cellulose acetate of high viscositycharacteristics in the presence of an organic softening agent forcellulose acetate, at least partially saponifying the threads, andthereafter twisting the threads to a high degree.

16. Process for the production of crepe threads, which comprisesstretching cellulose derivative threads uniformly along their length anduntil a permanent elongation is attained in the presence of an organicsoftening agent for the substance of the threads and thereafter twistingthe threads to a high degree. V

17. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads uniformly along their length anduntil a permanent elongation is attained in the presence of an organicsoftening agent for the cellulose acetate to give them a tenacity of atleast 2 grams per denier and thereafter twisting the threads to a highdegree.

18. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads uniformly along their length anduntil a permanent elongation is attained in the presence of an organicsoftening agent for the cellulose acetate, saponifying the threads so asto effect a loss of weight between 5 and 20% of the cellulose acetateand thereafter twisting the threads to a high degree.

19. Process for the production of crepe threads, which comprisesstretching cellulose derivative threads uniformly along their length anduntil a permanent elongation is attained in the presence of an organicsoftening agent for the substance of the threads and thereafter twistingthe threads to a high degree while applying steam thereto at the pointwhere the twist is inserted.

20. Process for the production of crepe threads, which comprisesstretching cellulose acetate threads uniformly along their length anduntil a permanent elongation is attained in the presence of an organicsoftening agent for the cellulose acetate to give the threads a tenacityof at least 3 grams per denier, saponifying the threads so as to effecta loss of weight ofbetween 5 and 20% of the cellulose acetate andthereafter twisting the threads to a high degree while applying steamthereto at the point where the twist is inserted.

HENRY DREYFUS. ROBERT WIGHTON MONCRIEFF.

SIDNEY JAMES MENZER. THOMAS ECCLES.

